Human immunodeficiency virus (HIV) is a virus that attacks immune cells called CD4 cells, which are a type of T cell.
These are white blood cells that move around the body, detecting faults and anomalies in cells as well as infections. When HIV targets and infiltrates these cells, it reduces the body’s ability to combat other diseases.
This increases the risk and impact of opportunistic infections and cancers. However, a person can carry HIV without experiencing symptoms for a long time.
HIV is a lifelong infection. However, receiving treatment and managing the disease effectively can prevent HIV from reaching a severe level and reduce the risk of a person passing on the virus.
What is AIDS?
AIDS is the most advanced stage of HIV infection. Once HIV infection develops into AIDS, infections and cancer pose a greater risk.
Without treatment, HIV infection is likely to develop into AIDS as the immune system gradually wears down. However, advances in ART mean than an ever-decreasing number of people progress to this stage.
By the close of 2015, around 1,122,900 people were HIV-positive. To compare, figures from 2016 show that medical professionals diagnosed AIDS in an estimated 18,160 people.
People transmit HIV in bodily fluids, including:
- vaginal secretions
- anal fluids
- breast milk
In the United States, the main causes of this transfer of fluids are:
- anal or vaginal intercourse with a person who has HIV while not using a condom or PrEP, a preventive HIV medication for people at high risk of infection
- sharing equipment for injectable illicit drugs, hormones, and steroids with a person who has HIV
- A woman living with HIV who is pregnant or has recently given birth might transfer the disease to her child during pregnancy, childbirth, or breastfeeding.
The risk of HIV transmitting through blood transfusions is extremely low in countries that have effective screening procedures in place for blood donations.
Undetectable = untransmittable
“To transmit HIV, these fluids must contain enough of the virus. If a person has ‘undetectable’ HIV, they will not transmit HIV to another person, even if after a transfer of fluids.
Undetectable HIV is when the amount of HIV in the body is so low that a blood test cannot detect it. People may be able to achieve undetectable levels of HIV by closely following the prescribed course of treatment.
Confirming and regularly monitoring undetectable status using a blood test is important, as this does not mean that the person no longer has HIV. Undetectable HIV relies on the person adhering to their treatment, as well as the effectiveness of the treatment itself.”
Progression to AIDS
The risk of HIV progressing to AIDS varies widely between individuals and depends on many factors, including:
- the age of the individual
- the body’s ability to defend against HIV
- access to high-quality, sanitary healthcare
- the presence of other infections
- the individual’s genetic inheritance resistance to certain strains of HIV
- drug-resistant strains of HIV
For the most part, infections by other bacteria, viruses, fungi, or parasites cause the more severe symptoms of HIV.
These conditions tend to progress further in people who live with HIV than in individuals with healthy immune systems. A correctly functioning immune system would protect the body against the more advanced effects of infections, and HIV disrupts this process.
Sweats are an early sign of HIV, but many people do not know they have the disease for years.
Some people with HIV do not show symptoms until months or even years after contracting the virus.
However, around 80 percent of people may develop a set of flu-like symptoms known as acute retroviral syndrome around 2–6 weeks after the virus enters the body.
The early symptoms of HIV infection may include:
- joint pain
- muscle aches
- sore throat
- sweats. particularly at night
- enlarged glands
- a red rash
- unintentional weight loss
These symptoms might also result from the immune system fighting off many types of viruses.
However, people who experience several of these symptoms and know of any reason they might have been at risk of contracting HIV over the last 6 weeks should take a test.
In many cases, after the symptoms of acute retroviral syndrome, symptoms might not occur for many years.
During this time, the virus continues to develop and cause immune system and organ damage. Without medication that prevents the replication of the virus, this slow process can continue for an average of around 10 years.
A person living with HIV often experiences no symptoms, feels well, and appears healthy.
Complying rigidly to a course of ART can disrupt this phase and suppress the virus completely. Taking effective antiretroviral medications for life can halt on-going damage to the immune system.
Late-stage HIV infection
Without medication, HIV weakens the ability to fight infection. The person becomes vulnerable to serious illnesses. This stage is known as AIDS or stage 3 HIV.
Symptoms of late-stage HIV infection may include:
- blurred vision
- diarrhea, which is usually persistent or chronic
- dry cough
- a fever of over 100 °F (37 °C) lasting for weeks
- night sweats
- permanent tiredness
- shortness of breath, or dyspnea
- swollen glands lasting for weeks
- unintentional weight loss
- white spots on the tongue or mouth
During late-stage HIV infection, the risk of developing a life-threatening illness increases greatly. A person with late-stage HIV can control, prevent and treat serious conditions by taking other medications alongside HIV treatment.
Preventing OIs is key to extending life expectancy with late-stage HIV. Aside from managing HIV viral load with medications, a person who lives with the disease must take precautions, including the following steps:
- Wear condoms to prevent other STIs.
- Receive vaccinations for potential OIs. Discuss these with your primary care physician.
- Understand the germs in your surrounding environment that could lead to an OI. A pet cat, for example, could be a source of toxoplasmosis. Limit exposure and take precautions, such as wearing protective gloves while changing litter
- Avoid foods that are at risk of contamination, such as undercooked eggs, unpasteurized dairy and fruit juice, or raw seed sprouts.
- Do not drink water straight from a lake or river or tap water in certain foreign countries. Drink bottled water or use water filters.
- Ask your doctor about work, home, and vacation activities to limit exposure to potential OIs.
- Antibiotic, antifungal, or antiparasitic drugs can help treat an OI.
HIV and AIDS myths and facts
Many misconceptions circulate about HIV that are harmful and stigmatizing for people with the virus.
The following cannot transmit the virus:
- shaking hands
- touching unbroken skin
- using the same toilet
- sharing towels
- sharing cutlery
- mouth-to-mouth resuscitation or other forms of “casual contact”
- the saliva, tears, feces, and urine of a person with HIV
HIV blood tests and results
A doctor can test for HIV using a specific blood test. A positive result means that they have detected HIV antibody in the bloodstream. The blood is re-tested before a positive result is given.
After potential exposure to the virus, early testing and diagnosis is crucial and greatly improves the chances of successful treatment. Home testing kits are also available.
HIV might take 3 – 6 months to show up in testing, and re-testing may be necessary for a definitive diagnosis. People at risk of infection within the last 6 months can have an immediate test. The test provider will normally recommend another test within a few weeks.
When is it time to start taking HIV medicines?
People with HIV should start ART as soon as possible. In people with the following conditions, it’s especially important to start ART right away: pregnancy, AIDS, certain HIV-related illnesses and coinfections, and early HIV infection. (Early HIV infection is the period up to 6 months after infection with HIV.)
Here are some things health care providers discuss with their patients before prescribing HIV medicines.
Sometimes HIV medicines can cause side effects. Most side effects from HIV medicines are manageable, but a few can be serious. Overall, the benefits of HIV medicines far outweigh the risk of side effects. In addition, newer HIV regimens cause fewer side effects than regimens used in the past. As HIV treatment options continue to improve, people are less likely to experience side effects from their HIV medicines.
Side effects from HIV medicines can vary depending on the medicine and the person taking the medicine. People taking the same HIV medicine can have very different side effects. Some side effects, like headaches or occasional dizziness, may not be serious. Other side effects, such as swelling of the throat and tongue or liver damage, can be life-threatening. To learn more about potential side effects of HIV medicines and how to deal with them, read the AIDSinfo HIV Medicines and Side Effects fact sheet.
HIV medicines can interact with other HIV medicines in an HIV regimen. They can also interact with other medicines, vitamins, nutritional supplements, and herbal products. A drug interaction can reduce or increase a medicine’s effect on the body. Drug interactions can also cause unwanted side effects.
When HIV multiplies in the body, the virus sometimes mutates (changes form) and makes variations of itself. Variations of HIV that develop while a person is taking HIV medicines can lead to drug-resistant strains of HIV. HIV medicines that previously controlled a person’s HIV are not effective against the new, drug-resistant HIV. In other words, the person’s HIV continues to multiply.
Poor adherence to an HIV regimen—not taking HIV medicines every day and exactly as prescribed—increases the risk of drug resistance and treatment failure.
Prevention measures include:
- Knowing your HIV status as well as your partner’s.
- Using latex condoms correctly during every sexual encounter.
- Limiting the number of sexual partners.
- Abstaining from injectable drug use and never sharing needles or syringes.
- Seeking treatment immediately after suspected HIV exposure, since newer medications known as post-exposure prophylaxis (PEP) may prevent infection if started early.
- Reducing the chance of becoming infected by obtaining pre-exposure prophylaxis (PrEP), which is a daily pill taken by people at high risk for HIV because of their sexual behaviour or from injecting drugs.